Hi. Welcome to the forum! Glad you joined!
7 nesting boxes on the inside left 12’x12’
I'm confused by this. You probably mean 12" x 12" but how many chickens is this for? The standard ratio is one box for every 4 hens but I have a personal preference for a minimum of two nests. Why do you have 7 nests taking up valuable coop space? Is this just a laying box where your chickens sleep elsewhere? Where are you located so we have an idea about your winter weather? To me, this raises a lot of questions about whether you will have enough room for your chickens.
I also plan on drilling 4” holes from outside to each nesting box and having that hole closed with plexy glass up take eggs down closed. Would this make it to bright inside.
Different humans have different personal preferences for how dark a coop or a nest should be. Some people go so far as to hang a curtain across the front of a nest to make it darker. My personal preference is to have the coop and nest a bit dark as I think darker tends to calm them down. They still need enough light to see.
Others that I highly respect on here like Rosemary have different opinions. So I put this down to a human personal preference where the chickens don't really care that much.
The way I understand this you want to be able to reach into the nest from outside to remove an egg. Practically everyone does that on coops this small. One standard method to do that is to hang the nest on the outside of the coop so you don't take up as much coop space inside and have a lid on hinges that opens upward to retrieve the egg. You have to be a bit careful with these so rainwater doesn't get in the nest but they are very popular. My preference is to have the door hinged so it swings open horizontally. That can help with the rainwater issue.
No matter how you go about it, an opening on the outside into your coop is a potential place for predators and egg-eating critters to enter. You need to assure that you can lock it unless it is in a predator safe area.
I haven't seen your idea before on here. I don't know how much all that light will affect the chickens, if it does at all. If you address the rainwater and predator issues it should work.
So good luck and once again
